Up to now, as a single remote control unit that remote controls a plurality of domestic resident electric equipments, there has been known a preset remote control unit of a device maker designation system, a remote control unit that learns an infrared-ray command, etc.
However, in the conventional remote control units, although a plurality of devices can be controlled, most of the remote control units are designed in such a manner that operating buttons for each of those devices are arranged on the operating surface of the remote control unit as they are. This is, the number of buttons on the operating surface is increased more as the number of operatable devices is increased. This make it difficult to identify the buttons, resulting in a lowered operability. In particular, when the operator is an aged person or a visually handicapped person, the remote control unit thus structured causes the adjustment error of an air conditioning temperature or the adjustment error of the volume of a television to occur due to misoperation.
Furthermore, there is a case in which even if the same function such as a timer is provided in the respective devices, those devices must be controlled by different buttons for the same function. This also causes the operability to be lowered.
Also, there is a remote control unit of the type in which all the operation is conducted by the depression of the operating buttons such as a tact switch from the viewpoints of the size and costs. The remote control unit of this type makes the reality of the operator's operation poor whereby the degraded response induces misoperation.
Furthermore, there has been proposed a remote control unit as disclosed in Japanese Patent Unexamined Publication No. 8-88883. This remote control unit is designed in such a manner that pad-shaped buttons where a plurality of functions can be selected by one button for each of the devices are provided on the operating surface to apparently reduce the number of the operating buttons. However, although the number of buttons can be reduced, there has not yet been solved such problems in operability that it is difficult to understand the operating method because a plurality of functions are realized by one button, and that a button by which a device to be controlled is operated must be searched on the basis of a pattern instructed on the operating button.
Also, the remote control unit that controls a plurality of devices generally increases in use frequency in comparison with a remote control unit that controls a single device. For that reason, the remote control unit which is generally operated with a battery suffers from a problem that a battery useable time is shortened so that the battery must be frequently replaced by a new one.
In general, when the lighting device is turned on, in order to allow a large amount of infrared rays to be emitted from the lighting device, it is required that the infrared rays of an amount as large as they does not lose noises occurring at the time of turning on the lighting device are outputted from the remote control device to control the lighting device. Compared with such a lighting device, a device such as a television or an air conditioner enables stable communication with a smaller amount of light than the lighting device. In usual, in order to realize stable and sure control with respect to any devices, there are many cases in which the remote control unit that controls a plurality of devices is designed to output an infrared ray necessary for controlling the lighting device. As a result, as described above, with an increase in operation frequency and the amount of emitted light, a power consumption is increased, and the lifetime of the battery for the remote control unit is shortened.
As a measurement to prevent the lifetime of the battery from being shortened, there has been generally known that an infrared ray emission element that narrows a range in which the infrared ray is distributed is used in order to control a device located as far as possible with a little amount of light. However, because the distribution of the infrared ray is narrowed in range, the remote control unit needs to be directed to the device to be controlled with an extreme accuracy at the time of controlling the remote control unit, as a result of which an operator frequently feels stress.
The button manipulation causes the remote control unit to be vibrated by an operator's hand to slightly shift the center of an optical axis, resulting in a problem that communication cannot be conducted. In particular, in the case of an aged person, the power of his arms and fingers becomes weak because he/she is aged, with the result that large vibrations are caused so that those phenomenons remarkably appear.
Also, assuming that a scene where the remote control unit is used in a toilet, a bath room, or the like, there is a case where the operator does not want the remote control using his hands or cannot conduct the remote control for the reason that the operator's hands are unclean or wet, or other reasons. Thus, there is a strong demand that he/she wants to realize the operation according to the operator's intention without directly touching the switch.